Elastic Stress Model: Add Some Bounce to Your Simulations
Color scale represents the r-z
(i.e. radial-axial) component
of elastic stress. Swelling of
the extruded material is
A new elastic stress model has been squeezed into FLOW-3D. With this model it is possible to simulate the transient response of elastic-visco-plastic materials, which are materials that behave as elastic solids up to a certain yield stress, beyond which they behave like a viscous liquid. In FLOW-3D, the elastic stress is computed incrementally from one time step to the next, which makes it easy to simulate large deformations.
One example of this new feature is the ability to simulate the behavior of purely elastic bodies. For example, a rubbery ball, 4cm in diameter, whose elastic modulus is 10kPa and density is 1g/cm3, is bounced off a solid surface.
Another swell example is that of a viscoplastic, or Bingham, material being forced through an cylindrical die by a uniform pressure gradient, as shown at left. The material has an elastic modulus of 1kPa and a yielding stress of 0.1kPa and is forced through a 1cm diameter die:
Future model increments will add the ability to predict thermally induced stresses, as well as localized elastic regions and elastic solids interacting with fluids, all stretching the utility of FLOW-3D.